Synthesis and evaluation of styryl and azo-methine disperse dyes containing phthalimide unit

摘要

Novel Methine disperse dyes were synthesized from malononitrile dimer/ethyl cyanoacetate dimer as a starting material. Malononitrile was dimerised using metallic sodium in ethanol which is condensed with different aldehydes such as anisaldehyde, salicylaldehyde, DEMAP-aldehyde, N,N-diethylamino benzaldehyde & N,N-dimethyl aminobenzaldehyde in presence of a mild base like piperidine to get methine dyes which was then condensed with phthalic anhydride to form the final dyes. Similarly, N,N-dimethyl-4-nitrosoaniline with malononitrile/ethylcyanoacetate dimer in ethanol with catalytic amount of triethylamine and then condensing this intermediate with phthalic anhydride to get the final dyes.The photo-physical and thermal properties were measured. These dyes were evaluated on the synthetic fabric.